On the NRF51 series, all peripherals have a fixed I/O size
of 4KiB. Define NRF51_PERIPHERAL_SIZE and use it.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200504072822.18799-2-f4bug@amsat.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>